function switchImage(MAINIMAGE){

	if(window.document.images){
			document.images[MAINIMAGE].src="images/nav_" + MAINIMAGE + "_on.gif";
	}//end IE check

}//end function


//javascript:removeImage('testImage')
function removeImage(MAINIMAGE){

	if(window.document.images){
			document.images[MAINIMAGE].src="images/nav_" + MAINIMAGE + ".gif";
	}//end IE check

}//end function